JP4157123B2 - Emulsifier for emulsion polymerization, method for producing polymer emulsion, and polymer emulsion - Google Patents

Description

  The present invention relates to an emulsifier for emulsion polymerization used in emulsion polymerization, a method for producing a polymer emulsion using the emulsifier for emulsion polymerization, and a polymer emulsion obtainable by the production method.

  Conventionally, as nonionic emulsifiers for emulsion polymerization, polyoxyalkylene alkylphenyl ethers obtained by adding alkylene oxide to nonylphenol or octylphenol and polyoxyalkylene alkyl ethers obtained by adding alkylene oxide to higher alcohols are used alone or in combination. However, the stability of the polymer emulsion and the properties of the polymer film obtained from the emulsion are not always satisfactory, and many problems to be solved remain.

  Examples thereof include problems such as polymerization stability of the emulsion, mechanical stability of the obtained emulsion, chemical stability, freeze-thaw stability, pigment miscibility, and storage stability. In particular, the mechanical stability remains a problem to be improved.

  Furthermore, when a polymer film is prepared from the emulsion, the used emulsifier remains in the polymer film in a free state, causing problems such as poor water resistance and adhesion of the film. In addition, when the emulsion is broken down by means such as salting out or aciding out and the polymer is taken out, a large amount of emulsifier is contained in the waste water, which causes environmental pollution such as river pollution. Labor is needed.

  From this point of view, in order to improve the problems of conventional emulsifiers for emulsion polymerization, many reactive emulsifiers having a copolymerizable unsaturated group as a reactive group and a polyoxyalkylene chain as a hydrophilic group have been proposed. Emulsion polymerization has been attempted for various monomers. Emulsions using these reactive emulsifiers as emulsifiers have good stability during polymerization, and polymer films obtained from the emulsions exhibit excellent performance in water resistance, adhesiveness, heat resistance, and weather resistance. Yes (for example, Patent Documents 1 to 4).

However, problems with reactive emulsifiers derived from such alkylene oxides include the fact that unreacted alkylene oxide remains in the product, and substances that are highly carcinogenic or irritating as by-products. It is done. For example, it is known that harmful dioxane is generated during synthesis and toxic aldehydes are generated by oxidative decomposition of alkylene oxide chains. In recent years, sick house syndrome and VOC (volatile organic compound) problems are noisy. It is not preferable to use an emulsifier for emulsion polymerization containing aldehyde or the like in the production of the emulsion.
Japanese Patent Laid-Open No. 8-41112 Japanese Patent Laid-Open No. 4-50204 JP-A-63-319035 JP 62-104802 A

  The present invention has been made in view of the above circumstances, and its purpose is not to have a polyoxyalkylene chain as a hydrophilic group, to improve stability during emulsion polymerization, and to prevent water resistance of polymers and polymer films. An object of the present invention is to provide an emulsifier for reactive emulsion polymerization in which the properties, adhesiveness, heat resistance and weather resistance are remarkably improved.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that an emulsifier for emulsion polymerization having an allyl group as an unsaturated group having copolymerizability and a hydrophilic group portion being polyglycerin is suitable. The present invention has been found and reached the present invention.

That is, this invention is an emulsifier for emulsion polymerization characterized by containing the compound represented by following General formula (1).

(In the formula, R ₁ is an alkyl group or alkenyl group having 6 to 30 carbon atoms , R ₂ is a hydrogen atom or a methyl group, and n is 1 to 200. X ₁ and X ₂ are a hydrogen atom , Methyl, ethyl, propyl, isopropyl, butyl, isobutyl, secondary butyl, tertiary butyl, pentyl, isopentyl, secondary pentyl, neopentyl, tertiary pentyl, hexyl, Secondary hexyl group, heptyl group, secondary heptyl group, octyl group, 2-ethylhexyl group, secondary octyl group, nonyl group, secondary nonyl group, decyl group, secondary decyl group, undecyl group, secondary undecyl group, Dodecyl, secondary dodecyl, tridecyl, isotridecyl, secondary tridecyl, tetradecyl, secondary tetradecyl, hexadecyl, secondary hex Sadecyl, stearyl, icosyl, docosyl, tetracosyl, triacontyl, 2-butyloctyl, 2-butyldecyl, 2-hexyloctyl, 2-hexyldecyl, 2-octyldecyl, 2-hexyl 1 selected from a dodecyl group, a 2-octyldodecyl group, a 2-decyltetradecyl group, a 2-dodecylhexadecyl group, a 2-hexadecyloctadecyl group, a 2-tetradecyloctadecyl group, and a monomethyl branched-isostearyl group Species or two or more groups .)

  The emulsifier for emulsion polymerization of the present invention is at least one selected from the group consisting of the compound represented by the general formula (1) and other nonionic surfactants, anionic surfactants and cationic surfactants other than the compounds. It may be a mixture with various types of surfactants.

In addition, the method for producing the polymer emulsion of the present invention may be one or two selected from acrylic monomers, aromatic monomers, vinyl ester monomers, halogenated olefin monomers, conjugated diolefin monomers, ethylene, maleic anhydride and methyl maleate. The emulsifier for emulsion polymerization is used in an amount of 0.1 to 20% by weight with respect to more than one monomer , and the monomer is polymerized in an aqueous medium, or added to the polymer after the monomer polymerization. .

  And the polymer emulsion of this invention can be obtained by the manufacturing method of the said polymer emulsion.

The emulsifier for emulsion polymerization of the present invention is to contain a compound represented by the following general formula (1).

In the compound of the general formula (1), R ₁ represents a hydrocarbon group. Examples of the hydrocarbon group include an alkyl group and an alkenyl group.

  Examples of the alkyl group include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, secondary butyl, tertiary butyl, pentyl, isopentyl, secondary pentyl, neopentyl, tertiary pentyl, hexyl, secondary hexyl, heptyl, 2 Secondary heptyl, octyl, 2-ethylhexyl, secondary octyl, nonyl, secondary nonyl, decyl, secondary decyl, undecyl, secondary undecyl, dodecyl, secondary dodecyl, tridecyl, isotridecyl, secondary tridecyl, tetradecyl, secondary tetradecyl Hexadecyl, secondary hexadecyl, stearyl, icosyl, docosyl, tetracosyl, triacontyl, 2-butyloctyl, 2-butyldecyl, 2-hexyloctyl, 2-hexyldecyl, 2-octyldecyl, 2-hexyldecyl, - octyldodecyl, 2-decyltetradecyl, 2-dodecyl-hexadecyl, 2-hexadecyl octadecyl, 2-tetradecyl-octadecyl, monomethyl branched - and the like isostearyl group.

  Examples of the alkenyl group include vinyl, allyl, propenyl, butenyl, isobutenyl, pentenyl, isopentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tetradecenyl, oleyl and the like.

R ₁ may contain two or more types of the hydrocarbon groups described above.

Further, in the general formula (1), R ₁ is preferably an alkyl group or alkenyl group having 6 to 30 carbon atoms.

R ₁ is usually a residue obtained by removing an epoxide moiety from an α-olefin epoxide. Industrially produced α-olefin epoxides include AOE series manufactured by Daicel Chemical Industries, Eposizer series manufactured by Dainippon Ink & Chemicals, and Vikolox series manufactured by ARKEMA. These are examples of raw materials that can be suitably used for commercial production. Moreover, it is also possible to mix and use two or more of these.

In the general formula (1), R ₂ is a hydrogen atom or a methyl group, and X ₁ and X ₂ are a hydrogen atom or the hydrocarbon group described above. N is 1 to 200, preferably 2 to 50.

  Moreover, the polyglycerin part of General formula (1) may be connected in linear form, and may be connected in dendritic form as shown in FIG.

  In the emulsifier for emulsion polymerization of the present invention, it is advantageous that the molar ratio of the hydrocarbon group portion to the polyglycerin portion is 1: 1 to 5: 1.

[Synthesis Method of Emulsifier for Emulsion Polymerization]
The reaction conditions for obtaining the emulsifier for emulsion polymerization of the present invention are not particularly limited. For example, the reaction composition obtained after reacting α-olefin epoxy with allyl alcohol or methallyl alcohol in the presence of a catalyst. By introducing a polyglycerin moiety into the emulsion, the emulsifier for emulsion polymerization of the present invention can be obtained. Moreover, you may refine | purify by a well-known method as needed.

  Polyglycerin can be introduced into the hydrophobic group having a reactive group by applying a known production method of polyglycerin alkyl ether. The production method of polyglycerin alkyl ether is, for example, according to the method disclosed in JP 2001-114720 A, JP 2000-38365 A, JP 9-188755 A, JP 6-293688 A. Can do.

[Emulsion polymerization monomer]
Examples of the monomer that can be applied to the emulsion polymerization using the emulsifier for emulsion polymerization of the present invention include various monomers such as acrylic acid, methyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, and methyl methacrylate. Acrylic monomers such as acrylonitrile, acrylamide, and acrylic acid hydroxy ester, aromatic monomers such as styrene and divinylbenzene, vinyl ester monomers such as vinyl acetate, halogenated olefin monomers such as vinyl chloride and vinylidene chloride, butadiene, In addition to conjugated diolefin monomers such as isoprene and chloroprene, there are ethylene, maleic anhydride, methyl maleate and the like. The emulsifier for emulsion polymerization of the present invention can be used for emulsion polymerization or suspension polymerization of one or more of the above monomers.

[Polymerization conditions]
The polymerization initiator used in the emulsion polymerization reaction using the emulsifier for emulsion polymerization of the present invention may be a conventionally known one, such as hydrogen peroxide, potassium persulfate, azobisisobutyronitrile, benzoyl peroxide, etc. Is available. As the polymerization accelerator, sodium bisulfite, ferrous ammonium sulfate, and the like can be used. Further, as a chain transfer agent, mercaptans such as α-methylstyrene dimer, n-butyl mercaptan, t-dodecyl mercaptan, halogenated hydrocarbons such as carbon tetrachloride and carbon tetrabromide may be used.

  The amount of the emulsifier for emulsion polymerization of the present invention is usually 0.1 to 20.0% by weight based on the total monomers. In addition, More preferably, 0.2-10.0 weight% is suitable.

  The emulsifier for emulsion polymerization of the present invention alone can satisfactorily complete the emulsion polymerization, but other nonionic surfactants, anionic surfactants and cationic surfactants may be used in combination, thereby emulsion polymerization. The polymerization stability at the time can be improved, and the processing characteristics in the subsequent process can be improved.

  Such other nonionic surfactants, anionic surfactants and cationic surfactants are not particularly limited. For example, nonionic surfactants include polyoxyalkylene alkyl phenyl ether, polyoxyalkylene alkyl ether, fatty acid polyethylene glycol ether. And anionic surfactants include fatty acid soap, rosin acid soap, alkyl sulfonate, alkyl aryl sulfonate, alkyl sulfo succinate, polyoxyethylene alkyl sulfate, polyoxyethylene aryl Examples of the cationic surfactant include stearyl trimethyl ammonium, cetyl trimethyl ammonium, and lauryl trimethyl ammonium. The amount used is preferably 0.5 to 100 parts by weight, more preferably 5 to 60 parts by weight with respect to 100 parts by weight of the emulsifier for emulsion polymerization of the present invention. More preferably, it is 10-30 weight part.

  Moreover, a well-known protective colloid agent can be used together in order to improve the polymerization stability at the time of emulsion polymerization. Examples of protective colloid agents that can be used in combination include fully saponified polyvinyl alcohol (PVA), partially saponified PVA, hydroxyethyl cellulose, carboxymethyl cellulose, methyl cellulose, polyacrylic acid, and gum arabic.

  As another method of using the emulsifier for emulsion polymerization of the present invention, it can be added to the polymer after completion of polymerization in order to improve the stability of the polymer emulsion.

[Action, other]
The emulsifier for emulsion polymerization of the present invention has an allyl group which is a copolymerizable double bond in the hydrophobic group part of the molecule, and is excellent in copolymerizability with a polymerizable monomer, particularly a vinyl monomer, Easy to incorporate into polymer composition. Therefore, as a copolymerizable reactive emulsifier, the amount of the emulsifier present in the polymer film obtained from the polymer emulsion is remarkably reduced, and the water resistance, adhesiveness, heat resistance and weather resistance of the film are greatly improved. Exhibits excellent effects. In addition, foaming and mechanical stability of the polymer emulsion are remarkably improved.

  Furthermore, a polymer emulsion free from harmful substances such as dioxane and aldehydes can be obtained.

  The polymer emulsion obtained by adding the emulsifier for emulsion polymerization of the present invention can be applied to wood, metal, paper, cloth, other concrete, etc. as, for example, an adhesive, a coating agent, and an impregnation reinforcing agent. The polymer taken out from the emulsion or latex can be used as a resin, rubber, polymer modifier or the like.

  Hereinafter, although an embodiment of the present invention is described by an example and a comparative example, the present invention is not limited at all by this. In the text, “parts” are based on weight unless otherwise specified.

<Production Example 1>
A reactor equipped with a stirrer, a nitrogen introduction tube, and a thermometer was charged with 87 parts of allyl alcohol and boron trifluoride ether complex as a catalyst, and an α-olefin epoxide having 12 or 14 carbon atoms (AOE X24, Daicel Chemical Industries ( 196 parts) were added dropwise, and the reaction was stirred at 80 ° C. for 5 hours. Next, the temperature was raised to 120 ° C., and excess allyl alcohol was removed by decompression. Next, potassium hydroxide was added as a catalyst to the obtained reaction composition, and 370 parts of glycidol was added dropwise at 120 ° C. over 1 hour, followed by further stirring for 2 hours. Finally, water is added to the polyglycerin adduct obtained in the above reaction to pass through a cation exchange resin and an anion exchange resin for desalting, followed by dehydration under reduced pressure to obtain an emulsifier A for emulsion polymerization according to the present invention. It was.

<Production Example 2>
A reactor equipped with a stirrer, a nitrogen inlet tube, and a thermometer was charged with 87 parts of allyl alcohol and potassium hydroxide as a catalyst, and an α-olefin epoxide having 12 or 14 carbon atoms (Eposizer M-24, Dainippon Ink & Chemicals, Inc.). 196 parts) were added dropwise, and stirred at 80 ° C. for 5 hours. Next, the temperature was raised to 120 ° C., and excess allyl alcohol was removed by decompression. Next, 740 parts of glycidol was added dropwise at 120 ° C. over 1 hour and the mixture was further stirred for 2 hours. Finally, water is added to the polyglycerin adduct obtained by the above reaction to pass through a cation exchange resin and an anion exchange resin for desalting, followed by dehydration under reduced pressure to obtain an emulsifier B for emulsion polymerization according to the present invention. It was.

<Production Example 3>
According to the method of Production Example 2, the reaction and purification were performed under the same conditions except that 1480 parts of glycidol was used, to obtain an emulsifier C for emulsion polymerization according to the present invention.

<Production Example 4>
A reactor equipped with a stirrer, a nitrogen inlet tube, and a thermometer was charged with 108 parts of methallyl alcohol and potassium hydroxide as a catalyst, and 212 parts of an α-olefin epoxide having 14 carbon atoms (Vikolox14, manufactured by ALKEMA) was dropped. The reaction was stirred at 80 ° C. for 5 hours. Next, the temperature was raised to 120 ° C., and excess methallyl alcohol was removed by decompression. Next, 2960 parts of glycidol was added dropwise at 120 ° C. over 1 hour and the mixture was further stirred for 2 hours. Finally, sulfuric acid was added to the polyglycerin adduct obtained by the above reaction for neutralization and dehydration, and then the precipitate was filtered to obtain an emulsifier D for emulsion polymerization of the present invention.

<Production Example 5>
According to the method of Production Example 2, the same conditions except that 252 parts of an α-olefin epoxide having 16 and 18 carbon atoms (Eposizer M-68, manufactured by Dainippon Ink & Chemicals, Inc.) and 4440 parts of glycidol were used. To obtain an emulsifier E for emulsion polymerization of the present invention.

<Production Example 6>
According to the method of Production Example 4, the reaction was carried out under the same conditions except that 252 parts of an α-olefin epoxide having 16 and 18 carbon atoms (AOE X68, manufactured by Daicel Chemical Industries, Ltd.) and 7400 parts of glycidol were used. Emulsifier F for emulsion polymerization of the product of the present invention was obtained by summing.

<Production Example 7>
According to the method of Production Example 1, an emulsifier for emulsion polymerization of the product of the present invention by reaction and purification under the same conditions except that 198 parts of a branched α-olefin epoxide having 12 to 14 carbon atoms and 1480 parts of glycidol were used. G was obtained.

<Production Example 8>
According to the method of Production Example 4, emulsifier H for emulsion polymerization of the present invention by reacting and neutralizing under the same conditions except that 240 parts of branched α-olefin epoxide having 16 carbon atoms and 2960 parts of glycidol were used. Got.

<Examples and Comparative Examples>
Table 1 shows emulsifiers for emulsion polymerization used in Examples and Comparative Examples. Comparative products A to F are conventional emulsifiers for emulsion polymerization to which ethylene oxide having the chemical structure shown in Table 1 is added.

<Usage example 1>
A mixed monomer emulsion was prepared by mixing 100 parts of butyl acrylate, 100 parts of styrene, 290 parts of ion-exchanged water and 10 parts of an emulsifier for emulsion polymerization, and dissolved oxygen was removed with nitrogen gas. Next, a reactor equipped with a stirrer, a reflux condenser, a thermometer and a dropping funnel was charged with 100 parts of the above mixed monomer emulsion, heated to 80 ° C., and 0.5 parts of potassium persulfate was added for prepolymerization. I let you. Next, over 10 hours after 10 minutes from the start of polymerization, 400 parts of the remaining mixed monomer emulsion was added dropwise for polymerization. Further, after aging for 2 hours at the polymerization temperature, the mixture was cooled to obtain a polymer emulsion.

  The emulsifiers for emulsion polymerization used are as shown in Table 2. Further, 10% by weight of the emulsifier for emulsion polymerization was used as a combined anionic emulsifier, and lauryl sulfate sodium salt was used.

  The contents of dioxane and formaldehyde as the emulsifier for emulsion polymerization used, and the obtained polymer emulsion were evaluated for polymerization stability, mechanical stability, particle diameter, foamability, and gloss of the film. The evaluation method is as follows. The results are shown in Table 2.

[Contents of dioxane and formaldehyde]
The dioxane contained in the emulsifier for emulsion polymerization was determined by spectrophotometry using GC and formaldehyde using the acetylacetone method. As a result, the dioxane amount was shown as less than 1 ppm: ○, 1-10 ppm: Δ, 10 ppm or more: ×, and the formaldehyde amount was less than 1 ppm: ○, 1-10 ppm: Δ, 10 ppm or more: ×.

[Polymerization stability]
The polymer emulsion after polymerization was filtered using an 80-mesh filter cloth, and the residue on the filter cloth was washed with water and dried, and the weight was expressed as a percentage of the solid content of the emulsion.

[Machine stability]
50 g of the polymer emulsion was stirred for 5 minutes at a load of 10 kg at a rotation speed of 1000 rpm with a Marlon type tester, the resulting agglomerate was filtered through an 80-mesh wire mesh, the residue was washed with water and dried, and its weight was determined as the solid content of the emulsion. In%.

[Particle size]
It measured with the dynamic light-scattering type particle size distribution measuring apparatus (MICROTRAC UPA 9340 made by Nikkiso) and displayed in μm.

[Foaming]
The emulsion was diluted 2 times with water, put in 30 cc into a 100 ml Nessler tube, inverted 30 times, and then measured for the amount of foam 5 minutes after standing, and expressed in ml.

[Glossiness of film]
A 0.5 mm (wet) emulsion film was formed on a glass plate and allowed to stand at room temperature for 24 hours to prepare a film. The glossiness of this film was visually evaluated in three stages: ○ (excellent), Δ (possible), and × (impossible).

<Usage example 2>
A reactor equipped with a stirrer, reflux condenser, thermometer and dropping funnel was charged with 135 parts of ion-exchanged water and 0.5 part of sodium bicarbonate as a buffering agent, heated to 80 ° C. Dissolved oxygen was removed. Separately, 75 parts of methyl methacrylate, 171 parts of ethyl acrylate, 4 parts of acrylic acid, 8 parts of an emulsifier for emulsion polymerization, and 110 parts of ion-exchanged water were mixed to prepare a monomer emulsion. Next, 40 parts of the monomer emulsion prepared above were added all at once to the reaction vessel, and after stirring for 10 minutes, 0.5 part of ammonium persulfate as a polymerization initiator was added and stirred for 10 minutes. Next, the remaining monomer emulsion was added dropwise over 3 hours to conduct a polymerization reaction, cooled to 40 ° C., and adjusted to pH 8-9 with aqueous ammonia to obtain a polymer emulsion.

  The emulsifiers for emulsion polymerization used are as shown in Table 3. Further, 10% by weight of the emulsifier for emulsion polymerization was used as a combined anionic emulsifier, and linear alkylbenzene sulfonic acid sodium salt was used.

  About the obtained polymer emulsion, polymerization stability, a particle diameter, the amount of VOC, the amount of unreacted emulsifier, and water resistance were evaluated, respectively. The evaluation methods for polymerization stability and particle diameter are the same as described above. The amount of VOC, the amount of unreacted emulsifier, and the water resistance evaluation method are as follows. The results are shown in Table 3.

[VOC amount]
The amount of VOC contained in the polymer emulsion was measured by headspace GC. As a result, it showed as less than 10 ppm: (circle), 10-50 ppm: (triangle | delta), 50 ppm or more: x.

[Unreacted emulsifier amount]
Methanol was added to the polymer emulsion to solidify the polymer, and after centrifugation, the amount of unreacted emulsifier was measured by HPLC-MS using the supernatant, and expressed in%.

[Water resistance test]
A polymer film having a thickness of 0.5 mm was prepared on a glass plate, immersed in water, and the time until 4.5 point characters could not be read through the polymer film was measured. The results are shown as 300 hours or more: ○, 300 to 200 hours: Δ, less than 200 hours: x.

<Usage example 3>
A reactor equipped with a stirrer, a reflux condenser, a thermometer, and a dropping funnel was charged with 250 parts of ion-exchanged water, heated to 80 ° C., and dissolved oxygen in water was removed with nitrogen gas. Next, 50 parts of a mixed monomer solution prepared by dissolving 5 parts of an emulsifier for emulsion polymerization in 125 parts of butyl acrylate and 125 parts of 2-ethylhexyl acrylate was charged into the reactor, and then 0.5 part of ammonium persulfate was added to the reactor. Polymerization was performed, and the remaining 205 parts of the mixed monomer solution was added dropwise over 3 hours from 10 minutes after the start of the polymerization. Subsequently, the mixture was further aged for 2 hours at the polymerization temperature, cooled to 40 ° C., and adjusted to pH 8-9 with aqueous ammonia to obtain a polymer emulsion.

  The emulsifiers for emulsion polymerization used are as shown in Table 4. Further, 10% by weight of the emulsifier for emulsion polymerization was used as a combined anionic emulsifier, and polyoxyethylene styrenated phenyl ether phosphate ester (EO 8 mol adduct) was used.

  About the obtained polymer emulsion, polymerization stability, mechanical stability, the amount of unreacted emulsifier, heat-resistant coloring property, and adhesiveness were evaluated, respectively. The evaluation methods for polymerization stability, mechanical stability, and amount of unreacted emulsifier are the same as described above. The evaluation methods for heat resistant colorability and adhesiveness are as follows. The results are shown in Table 4.

[Heat resistant coloring]
A polymer film having a thickness of 0.5 mm was prepared on a glass plate, heat-treated for 30 minutes in a hot air drier adjusted to 200 ° C., and coloring of the polymer film was visually observed. As a result, no coloration was observed: ○, pale yellow coloration: Δ, dark brown coloration: x.

[Adhesiveness]
The emulsion is applied to a thickness of 25 μm (dry) on a PET film cut to a width of 5 cm, heat-treated, then attached to a SUS plate, and roller-pressed. The film was peeled off so that the adhesive surface was 5 cm × 5 cm, and a time (second) until the film was peeled off by hanging a weight of 200 g on the edge of the film was measured.

<Usage example 4>
A reactor equipped with a stirrer, reflux condenser, thermometer and dropping funnel was charged with 131 parts of ion-exchanged water and 0.5 part of sodium bicarbonate as a buffering agent, heated to 70 ° C. Dissolved oxygen was removed. Separately, 250 parts of vinyl acetate, 8 parts of an emulsifier for emulsion polymerization, and 110 parts of ion-exchanged water were mixed to prepare a monomer emulsion. Next, 40 parts of the monomer emulsion prepared above were added all at once to the reaction vessel, and after stirring for 10 minutes, 0.5 part of ammonium persulfate as a polymerization initiator was added and stirred for 10 minutes. Next, the remaining monomer emulsion was added dropwise over 3 hours to conduct a polymerization reaction, cooled to 40 ° C., and adjusted to pH 8-9 with aqueous ammonia to obtain a polymer emulsion.

  The emulsifiers for emulsion polymerization used are as shown in Table 5.

  The obtained polymer emulsion was evaluated for polymerization stability, particle diameter, and adhesiveness. The polymerization stability and particle size evaluation method is the same as the above evaluation method. The evaluation method of adhesiveness is as follows. The results are shown in Table 5.

[Adhesiveness]
The emulsion is applied to a plywood cut to a width of 5 cm to a thickness of 25 μm (dry), heat-treated, and then a 5 cm-wide cotton cloth is attached thereto, followed by roller pressure bonding. The cloth was peeled off so that the adhesion surface became 5 cm × 5 cm, and a time (second) until the piece was peeled off by hanging a 1 kg weight on the edge of the peeled cloth was measured.

  From the results of Tables 2 to 5, the emulsifier for emulsion polymerization according to the present invention has a very small amount of aldehyde and dioxane contained in the emulsifier, good polymerization stability and mechanical stability of the emulsion, and harmful such as VOC. Generation of by-products can be reduced. In addition, the amount of unreacted emulsifier is small, and it can be seen that the obtained polymer emulsion has superior properties such as film gloss, adhesion, and water resistance compared to those using a conventional nonionic surfactant emulsifier. .

  The polymer emulsion obtained by the present invention can be applied to wood, metal, paper, cloth, and other concrete as an adhesive, a coating agent, an impregnation reinforcing agent, and the like. The polymer taken out from the emulsion or latex can be used as a resin, rubber, polymer modifier or the like.

It is a schematic structure figure which shows one example in which the polyglycerin part was connected in dendritic form.

Claims (4)

An emulsifier for emulsion polymerization comprising a compound represented by the following general formula (1).

(In the formula, R ₁ is an alkyl group or alkenyl group having 6 to 30 carbon atoms , R ₂ is a hydrogen atom or a methyl group, and n is 1 to 200. X ₁ and X ₂ are a hydrogen atom , Methyl, ethyl, propyl, isopropyl, butyl, isobutyl, secondary butyl, tertiary butyl, pentyl, isopentyl, secondary pentyl, neopentyl, tertiary pentyl, hexyl, Secondary hexyl group, heptyl group, secondary heptyl group, octyl group, 2-ethylhexyl group, secondary octyl group, nonyl group, secondary nonyl group, decyl group, secondary decyl group, undecyl group, secondary undecyl group, Dodecyl, secondary dodecyl, tridecyl, isotridecyl, secondary tridecyl, tetradecyl, secondary tetradecyl, hexadecyl, secondary hex Sadecyl, stearyl, icosyl, docosyl, tetracosyl, triacontyl, 2-butyloctyl, 2-butyldecyl, 2-hexyloctyl, 2-hexyldecyl, 2-octyldecyl, 2-hexyl 1 selected from dodecyl, 2-octyldodecyl, 2-decyltetradecyl, 2-dodecylhexadecyl, 2-hexadecyloctadecyl, 2-tetradecyloctadecyl, and monomethyl branched-isostearyl groups Species or two or more groups .)   A mixture of the compound represented by the general formula (1) and at least one surfactant selected from the group of other nonionic surfactants, anionic surfactants and cationic surfactants other than the compounds; The emulsifier for emulsion polymerization according to claim 1, wherein the emulsifier is used for emulsion polymerization. Claim 1 or 2 for one or more monomers selected from acrylic monomers, aromatic monomers, vinyl ester monomers, halogenated olefin monomers, conjugated diolefin monomers, ethylene, maleic anhydride and methyl maleate An emulsion for emulsion polymerization as described in 1) is used in an amount of 0.1 to 20% by weight, and the monomer is polymerized in an aqueous medium, or added to the polymer after the monomer polymerization, to produce a polymer emulsion Method.   A polymer emulsion obtained by the method for producing a polymer emulsion according to claim 3.

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